A small fix needed to make pismi.py behave

Before this it always created both foo.nc and foo.nc~ and failed to write *all* of its
outputs to foo.nc (some ended up in foo.nc~).

examples/inverse/pismi.py

@@ -1,6 +1,6 @@
 #! /usr/bin/env python3
 #
-# Copyright (C) 2011, 2012, 2013, 2014, 2015, 2016, 2017, 2018, 2019, 2020 David Maxwell and Constantine Khroulev
+# Copyright (C) 2011, 2012, 2013, 2014, 2015, 2016, 2017, 2018, 2019, 2020, 2021 David Maxwell and Constantine Khroulev
 #
 # This file is part of PISM.
 #
@@ -567,8 +567,8 @@ def run():
     vecs.add(residual, writing=True)
     vecs.add(r_mag, writing=True)
 
-    # Write solution out to netcdf file
-    forward_run.write(output_filename, append=append_mode)
+    # Write solution out to netcdf file (always append because the file was created already)
+    forward_run.write(output_filename, append=True)
     # If we're not in append mode, the previous command just nuked
     # the output file.  So we rewrite the siple log.
     if not append_mode:

site-packages/PISM/ssa.py

@@ -124,14 +124,15 @@ def solve(self):
 
         return self.ssa.velocity()
 
-    def write(self, filename):
+    def write(self, filename, append=False):
         """Saves all of :attr:`modeldata`'s vecs (and the solution) to an
         output file."""
         grid = self.grid
         vecs = self.modeldata.vecs
 
-        pio = util.prepare_output(filename)
-        pio.close()
+        if not append:
+            pio = util.prepare_output(filename)
+            pio.close()
 
         # Save time & command line
         util.writeProvenance(filename)